1. Field of the Invention
This invention relates to a combustion powered tool device, more particularly to a dual safety combustion powered tool device.
2. Description of the Related Art
Referring to FIGS. 1 and 2, a combustion powered tool device 1 disclosed in U.S. Pat. No. 5,197,646 is shown to include a main housing 11 for accommodating a piston-driver blade assembly 16 which strikes a nail fed from a magazine out of a nose end 17 against a targeted surface when making a stroke movement caused by actuation of a trigger body 13. A lock-out pawl 14 has an end pivotally connected to the trigger body 13, and an opposite end. The opposite end is displaced in an aperture 151 of a valve sleeve member 152 when the valve sleeve member 152 is moved to a rearward combustion-chamber closed position, as a result of the engagement of a push member 15 with the targeted surface. At this stage, as shown in FIG. 2, the trigger body 13 is permitted to be moved to an actuating position. When the push member 15 is no longer pressed by the targeted surface and the valve sleeve member 152 is thereby displaced to a forward combustion-chamber opened position, as shown in FIG. 1, the pawl 14 is engaged with an external wall of the valve sleeve member 152, so that the trigger body 13 cannot be moved to the actuating position, thereby preventing undesirable firing of the combustion powered tool device 1.
However, during operation, if the push member 15 is not properly engaged with the targeted surface when the trigger body 13 is moved only halfway to the actuating position, and if the pawl 14 is displaced to engage the aperture 151 to permit the trigger body 13 to freely move, inadvertent continued triggering action by the user toward the actuating position might give rise to an undesirable firing.